<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
	<style type="text/css">
		*{
			margin: 0;
			padding: 0;
		}
		.box{
			width: 400px;
			height: 400px;
			display: flex;
			flex-wrap: wrap;
			margin: 100px auto;
			animation:fengche 2s linear infinite;
		}
		.a{
			width: 0px;
			height: 0px;
/*			border-left:200px solid transparent;*/
			border-right:200px solid transparent;
			border-bottom:200px solid red;
		}
		.b{
			width: 0;
			height: 0;
/*			border-left:200px solid transparent;*/
			border-right: 200px solid transparent;
			border-top: 200px solid black;
		}
		.c{
			width: 0;
			height: 0;
			border-top: 200px solid transparent;
/*			border-bottom: 200px solid transparent;*/
			border-right: 200px solid blue;
		}
		.d{
			width: 0;
			height: 0;
/*			border-top:50px solid transparent;*/
			border-bottom:200px solid transparent;
			border-right:200px solid orange;
		}

		@keyframes fengche{
			100%{

				transform: rotate(360deg); 
			}
		}

		

	</style>
</head>
<body>
	<div class="box">
		<div class="a"></div>
		<div class="b"></div>
		<div class="c"></div>
		<div class="d"></div>
	</div>


</body>
</html>